Molecular recognition (also called a binding event) is fundamental to every cellular event: transcription, translation, signal transduction, viral and bacterial infection and immune response are all mediated by selective recognition events. Thus, developing a better understanding of detecting the binding events of molecules is of significant importance.
Typical methods for carrying out on-chip analyte detections include: optical tagging (fluorescence, visible, IR, Raman), radiometric (various radioactive tag), and indirect electrochemical methods of detection (tagging with enzymes that generate charges that can be measured).
Polymer arrays are currently manufactured by three principal methods. One method employs printing/spotting technologies to deliver preformed polymers onto attachment sites on the surface of a given substrate, most often ones composed of glass or quartz (e.g., see the methods of Agilent.com). Quality controls for these attachment reactions that have been approached by this manufacturing method are necessarily indirect. For example, attachment can be measured by including fluorescently tagged polymers into the reaction mixture that is spotted on the arrays so that binding can be detected by optical methods. Alternately, attached polymers can be detected by binding fluorescently tagged probes to the attached polymers
Another method for the manufacture of polymer arrays is to use photolithographic methods to grow the polymers in situ. However, as with the printing methods described above, the photolithographic manufacturing processes are carried out on glass or quartz substrates.